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<a name="wp7396"></a><h1 class="pHeading2 FontLevel1" id="MGC7396">

<a name="CRefID35088"></a>
SPECCTRA Link
</h1>
<a name="wp7398"></a><p class="pBody">


The SPECCTRA Link sends PCB design file data to a SPECCTRA design file, and then imports the SPECCTRA results back to a PCB design file. SPECCTRA translates route protection status, physical design reuses, test point settings on both vias and component pins, decal keepouts, board keepouts, and board cutouts. Route protection status is passed to and from SPECCTRA for routed traces and vias using SPECCTRA&#39;s <span class=" cItalic">fix</span> attribute for wires and <span class=" cItalic">route</span> attribute for vias. Protection for unrouted traces is passed to SPECCTRA only for whole connections, such as routed links that start and end on component pins. For more information, see <a href="xlater2.html#wp7439"  onclick='oT("CRF","xlater2.html#wp7439");return false;'>&quot;Passing Route Protection Status to SPECCTRA&quot;</a>.
</p>

<a name="wp7402"></a><p class="pBody">

When you use the SPECCTRA command from the Tools menu, you can run the entire process of converting, routing, and reloading into PADS Layout automatically. 
</p>

<a name="wp7403"></a><p class="pBody">

To control the SPECCTRA interface you can also start the Link and SPECCTRA executables manually. When you run SPECCTRA manually, you can choose the conversion direction: TO SPECCTRA or FROM SPECCTRA.
</p>

<a name="wp7404"></a><p class="pBody">

The Link features an automatic DO File editor to edit existing or new DO files. Parameters are automatically saved between sessions. 
</p>

<a name="wp7407"></a><h2 class="pHeading3NoSplit FontLevel2" id="MGC7407">

<a name="CRefID53878"></a>
Unused Pins Net


</h2>
<a name="wp7408"></a><p class="pBody">

PADS Layout passes unused pins, or pins that are not connected to a net, to SPECCTRA. These pins and their fanouts are added to a net of unused pins called +UNUSED_PINS+ in SPECCTRA (this was formerly called *UNUSED_PINS*). When you return the routed design to PADS Layout, you can also pass the unused pins and fanout information. The +UNUSED_PINS+ net information is translated into the NOT_CONNECTED net
 in PADS Layout. You can change the name of the NOT_CONNECTED net
 in the SPECCTRA Options dialog box, but the net should have a unique name. 
</p>

<a name="wp7412"></a><p class="pBody">

The NOT_CONNECTED net
 is a normal net inside PADS Layout that contains the fanout via, the trace, and the unused pin. Because this net is a normal net in PADS Layout, pins in it are no longer treated as unused pins in subsequent SPECCTRA sessions. Use the existing DO file to protect this net from being routed as a normal net in subsequent sessions. To recreate this net in SPECCTRA, delete it in PADS Layout before routing the design. 
</p>

<a name="wp8698"></a><p class="pBody">

<span class=" cBold">Tip: </span>PADS Layout cannot define a connection for a single pin net; therefore, if the +UNUSED_PINS+ net contains only a single component pin and fanout, PADS Layout cannot interpret it.
</p>

<a name="wp7414"></a><p class="pBody">

<a href="xlater2.html#wp8713"  onclick='oT("CRF","xlater2.html#wp8713");return false;'>Figure&#160;13-1</a> demonstrates fanouts on unused pins in SPECCTRA. It also demonstrates how PADS Layout interprets those fanouts and unused pins. Because SPECCTRA now translates test point attributes on component pins as well as on vias, the following figure demonstrates how SPECCTRA passes test points assigned to the fanouts of the unused pins.
</p>

<a name="wp8713"></a><p class="pFigureTitle" id="MGC8713">

Figure 13-1. 
Fanouts on Unused Pins<a name="CRefID60047"></a><a name='Graphic8714'></a>
<img src="images/xlater1a.png"   height='123' width='502' class="Aligncenter" id='wp8714' border='0' hspace='0' vspace='0'/>

</p>


<a name="wp7419"></a><h2 class="pHeading3NoSplit FontLevel2" id="MGC7419">

<a name="CRefID49968"></a>
Passing Data to SPECCTRA
</h2>
<a name="wp7420"></a><h3 class="pHeading4 FontLevel3" id="MGC7420">


Passing DFT Audit Settings to SPECCTRA
</h3>
<a name="wp7423"></a><p class="pBody">




You can pass DFT Audit test point placement options to SPECCTRA for its test point placement routine. SPECCTRA generally uses these options when applicable. Options such as test point clearances are passed to SPECCTRA. But options such as nail diameters and fixture drill sizes are used only by DFT Audit. Because they do not affect SPECCTRA&#39;s test point insertion, this type of information is not passed. 
</p>

<a name="wp7424"></a><p class="pBody">

SPECCTRA bases its clearance calculations on DFT Audit options. SPECCTRA&#39;s clearance options are set in the Setup Test Point Rule area of the SPECCTRA DO File dialog box. For more information about DFT Audit, see <a name="EW32"></a><a href="check09.html#CRefIDDesign for Test" onclick='oT("CRF","check09.html#CRefIDDesign for Test");'><span class=" cLinkOverride">&ldquo;Design for Test&rdquo;</span></a>.
</p>

<a name="wp8662"></a><p class="pBody">

<span class=" cBold">Tip: </span>SPECCTRA does not allow assigning multiple test points to net. This setting is not passed to SPECCTRA.
</p>

<a name="wp7429"></a><h3 class="pHeading4 FontLevel3" id="MGC7429">


Passing Keepouts to SPECCTRA
</h3>
<a name="wp7432"></a><p class="pBody">



The PADS Layout to SPECCTRA Link supports via keepouts and passing other types of keepouts (for wires, bends, components, and pins) to SPECCTRA. Copper shapes on any level are passed in this way. By manipulating this existing keepout functionality, you can pass other specific keepouts to SPECCTRA.
</p>

<a name="wp7433"></a><p class="pBody">

PADS Layout supports keepouts in the Layout Editor.
</p>

<a name="wp7436"></a><h3 class="pHeading4 FontLevel3" id="MGC7436">


Passing Slotted Holes to SPECCTRA


</h3>
<a name="wp7437"></a><p class="pBody">

Nonplated slotted holes are converted to keepouts on all layers. Plated slotted holes use a circular drill at the electrical center.
</p>

<a name="wp7439"></a><h3 class="pHeading4 FontLevel3" id="MGC7439">

<a name="CRefID33246"></a>
Passing Route Protection Status to SPECCTRA
</h3>
<a name="wp7442"></a><p class="pBody">



You can set options in PADS Layout that prevent modifying routed traces and vias in SPECCTRA. This feature protects critically placed routes during interactive routing and in batch routing in automatic routers. Protection is passed to and from SPECCTRA. Components, vias, test points, and other design items associated with protected routes or unroutes are also protected. 
</p>

<a name="wp7443"></a><h3 class="pHeading4 FontLevel3" id="MGC7443">


Passing Protected Traces and Vias
</h3>
<a name="wp7447"></a><p class="pBody">




Routed traces with protected status are passed to SPECCTRA with a <span class=" cItalic">fix</span> attribute. You cannot modify fixed traces, and the router cannot route to this trace.
</p>

<a name="wp7448"></a><p class="pBody">

Vias attached to at least one protected trace are passed to SPECCTRA with a <span class=" cItalic">route</span> attribute. Although you cannot modify these vias, you can route to them to complete a connection.
</p>

<a name="wp7490"></a><p class="pBody">

<a href="xlater2.html#wp8731"  onclick='oT("CRF","xlater2.html#wp8731");return false;'>Table&#160;13-1</a> lists the rules used by the SPECCTRA Link to determine via attributes.
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8731"></a><p class="pTableTitle" id="MGC8731">

Table 13-1. 
SPECCTRA Link Rules&#160;<a name="CRefID69874"></a>
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8731table7449">
  <tr bgcolor="#CCCCCC"  align="center" valign="middle">
    <th>

<a name="wp7451"></a><p class="pTableHeading" id="MGC8731">
Via has protected traces
</p>
</th>

    <th>

<a name="wp7453"></a><p class="pTableHeading">

Locked test point status
</p>
</th>

    <th>

<a name="wp7455"></a><p class="pTableHeading">

Glue status
</p>
</th>

    <th>

<a name="wp7457"></a><p class="pTableHeading">

SPECCTRA via status
</p>
</th>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:1.57in'>


<a name="wp7459"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row2Column2'  style='width:1.32in'>


<a name="wp7461"></a><p class="pTableCell">
Any</p></td>

    <td id='Row2Column3'  style='width:1.25in'>


<a name="wp7463"></a><p class="pTableCell">
Any</p></td>

    <td id='Row2Column4'  style='width:1.86in'>


<a name="wp7465"></a><p class="pTableCell">
Route</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7467"></a><p class="pTableCell">
No</p></td>

    <td id='Row3Column2' >


<a name="wp7469"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row3Column3' >


<a name="wp7471"></a><p class="pTableCell">
Any</p></td>

    <td id='Row3Column4' >


<a name="wp7473"></a><p class="pTableCell">
Route</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7475"></a><p class="pTableCell">
No</p></td>

    <td id='Row4Column2' >


<a name="wp7477"></a><p class="pTableCell">
No</p></td>

    <td id='Row4Column3' >


<a name="wp7479"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row4Column4' >


<a name="wp7481"></a><p class="pTableCell">
Protect</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row5Column1' >


<a name="wp7483"></a><p class="pTableCell">
No</p></td>

    <td id='Row5Column2' >


<a name="wp7485"></a><p class="pTableCell">
No</p></td>

    <td id='Row5Column3' >


<a name="wp7487"></a><p class="pTableCell">
No</p></td>

    <td id='Row5Column4' >


<a name="wp7489"></a><p class="pTableCell">
Normal (by default)</p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pBody">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7491"></a><h3 class="pHeading4 FontLevel3" id="MGC7491">


Passing Protected, Unrouted Traces
</h3>
<a name="wp7493"></a><p class="pBody">


Route protection status is passed to SPECCTRA only for those PADS Layout unrouted traces that are whole connections, which start and end on component pins. Unrouted connections are passed to SPECCTRA as a <span class=" cItalic">fromto</span> with a <span class=" cItalic">fix</span> attribute.
</p>

<a name="wp7494"></a><h3 class="pHeading4 FontLevel3" id="MGC7494">


Passing Protected Components with Routed Traces
</h3>
<a name="wp7497"></a><p class="pBody">



A component is passed to SPECCTRA with <span class=" cItalic">lock</span> status as long as the component has at least one pin attached to a trace with route protection.
</p>

<a name="wp7498"></a><h3 class="pHeading4 FontLevel3" id="MGC7498">


Receiving Protection Status for Routed Traces from SPECCTRA
</h3>
<a name="wp7501"></a>
<ul><li class="LL1BulSolid">

SPECCTRA wires that have a <span class=" cItalic">fix</span> attribute are returned to PADS Layout as traces with route protection. </li></ul>

<a name="wp7502"></a>
<ul><li class="LL1BulSolid">Vias with a protect attribute in SPECCTRA are transformed to glued status in PADS Layout.</li></ul>

<a name="wp7503"></a>
<ul><li class="LL1BulSolid">Vias that have a <span class=" cItalic">route</span> attribute in SPECCTRA are not given special protection in PADS Layout.</li></ul>

<a name="wp7504"></a><p class="pBody">

<a href="xlater2.html#wp8749"  onclick='oT("CRF","xlater2.html#wp8749");return false;'>Table&#160;13-3</a> through <a href="xlater2.html#wp8763"  onclick='oT("CRF","xlater2.html#wp8763");return false;'>Table&#160;13-4</a> provide lists of the passing and returning protection status for PADS Layout traces, vias, and unroutes.
</p>

<a name="wp7576"></a><p class="pHTaskSubhead">

Traces
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8739"></a><p class="pTableTitle" id="MGC8739">

Table 13-2. 
Protection Status for Traces
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8739table7505">
  <tr bgcolor="#CCCCCC"  align="center" valign="middle">
    <th>

<a name="wp7507"></a><p class="pTableHeading" id="MGC8739">

<br />Status in 
<br />PADS Layout 
</p>
</th>

    <th>

<a name="wp7509"></a><p class="pTableHeading">


<br />Status passed to SPECCTRA
</p>
</th>

    <th>

<a name="wp7511"></a><p class="pTableHeading">

Protection in SPECCTRA
</p>
</th>

    <th>

<a name="wp7513"></a><p class="pTableHeading">

Status passed from SPECCTRA
</p>
</th>

    <th>

<a name="wp7515"></a><p class="pTableHeading">

Status returned to PADS Layout 
</p>
</th>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:1.19in'>


<a name="wp7517"></a><p class="pTableCell">
Regular trace</p></td>

    <td id='Row2Column2'  style='width:1.44in'>


<a name="wp7519"></a><p class="pTableCell">
Normal type wire</p></td>

    <td id='Row2Column3'  style='width:1.12in'>


<a name="wp7521"></a><p class="pTableCell">
---</p></td>

    <td id='Row2Column4'  style='width:1.13in'>


<a name="wp7523"></a><p class="pTableCell">
Normal type</p></td>

    <td id='Row2Column5'  style='width:1.12in'>


<a name="wp7525"></a><p class="pTableCell">
Regular trace</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7527"></a><p class="pTableCell">
Regular trace</p></td>

    <td id='Row3Column2' >


<a name="wp7529"></a><p class="pTableCell">
Normal type</p></td>

    <td id='Row3Column3' >


<a name="wp7531"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row3Column4' >


<a name="wp7533"></a><p class="pTableCell">
Protect type</p></td>

    <td id='Row3Column5' >


<a name="wp7535"></a><p class="pTableCell">
Regular trace</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7537"></a><p class="pTableCell">
Regular trace</p></td>

    <td id='Row4Column2' >


<a name="wp7539"></a><p class="pTableCell">
Normal type</p></td>

    <td id='Row4Column3' >


<a name="wp7541"></a><p class="pTableCell">
Fix</p></td>

    <td id='Row4Column4' >


<a name="wp7543"></a><p class="pTableCell">
Protect type</p></td>

    <td id='Row4Column5' >


<a name="wp7545"></a><p class="pTableCell">
Regular trace</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row5Column1' >


<a name="wp7547"></a><p class="pTableCell">
Protected trace</p></td>

    <td id='Row5Column2' >


<a name="wp7549"></a><p class="pTableCell">
Fix type</p></td>

    <td id='Row5Column3' >


<a name="wp7551"></a><p class="pTableCell">
---</p></td>

    <td id='Row5Column4' >


<a name="wp7553"></a><p class="pTableCell">
Fix type</p></td>

    <td id='Row5Column5' >


<a name="wp7555"></a><p class="pTableCell">
Protected trace</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row6Column1' >


<a name="wp7557"></a><p class="pTableCell">
Protected trace</p></td>

    <td id='Row6Column2' >


<a name="wp7559"></a><p class="pTableCell">
Fix type</p></td>

    <td id='Row6Column3' >


<a name="wp7561"></a><p class="pTableCell">
Protect/Unprotect</p></td>

    <td id='Row6Column4' >


<a name="wp7563"></a><p class="pTableCell">
Fix type</p></td>

    <td id='Row6Column5' >


<a name="wp7565"></a><p class="pTableCell">
Protected trace</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row7Column1' >


<a name="wp7567"></a><p class="pTableCell">
Protected trace</p></td>

    <td id='Row7Column2' >


<a name="wp7569"></a><p class="pTableCell">
Fix type</p></td>

    <td id='Row7Column3' >


<a name="wp7571"></a><p class="pTableCell">
Fix/unfix</p></td>

    <td id='Row7Column4' >


<a name="wp7573"></a><p class="pTableCell">
Fix type</p></td>

    <td id='Row7Column5' >


<a name="wp7575"></a><p class="pTableCell">
Protected trace</p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pHTaskSubhead">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7718"></a><p class="pHTaskSubhead">

Vias
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8749"></a><p class="pTableTitle" id="MGC8749">

Table 13-3. <a name="CRefID78462"></a>
Protection Status for Vias
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8749table7577">
  <tr align="left" valign="top">
    <td colspan="3" rowspan="1">

<a name="wp7579"></a><p class="pTableHeading" id="MGC8749">
Status of trace in PADS Layout
</p>
</td>

    <td id='Row1Column4'  style='width:1.09375in'>


<a name="wp7585"></a><p class="pTableCell">
  &#160;</p></td>

    <td id='Row1Column5'  style='width:1.09833in'>


<a name="wp7587"></a><p class="pTableCell">
  &#160;</p></td>

    <td id='Row1Column6'  style='width:1.08917in'>


<a name="wp7589"></a><p class="pTableCell">
  &#160;</p></td>

    <td id='Row1Column7'  style='width:0.9in'>


<a name="wp7591"></a><p class="pTableCell">
  &#160;</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:0.84375in'>


<a name="wp7593"></a><p class="pTableCell">
Has Protected Traces</p></td>

    <td id='Row2Column2'  style='width:0.78125in'>


<a name="wp7595"></a><p class="pTableCell">
Locked TP status</p></td>

    <td id='Row2Column3'  style='width:0.64583in'>


<a name="wp7597"></a><p class="pTableCell">
Glued Status</p></td>

    <td id='Row2Column4'  style='width:1.09375in'>


<a name="wp7599"></a><p class="pTableHeading">


<br />Status passed to SPECCTRA
</p>
</td>

    <td id='Row2Column5'  style='width:1.09833in'>


<a name="wp7601"></a><p class="pTableHeading">


<br />Protection in SPECCTRA
</p>
</td>

    <td id='Row2Column6'  style='width:1.08917in'>


<a name="wp7603"></a><p class="pTableHeading">

Status passed from SPECCTRA
</p>
</td>

    <td id='Row2Column7'  style='width:0.9in'>


<a name="wp7605"></a><p class="pTableHeading">


<br />Status returned to PADS Layout
</p>
</td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7607"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row3Column2' >


<a name="wp7609"></a><p class="pTableCell">
Any</p></td>

    <td id='Row3Column3' >


<a name="wp7611"></a><p class="pTableCell">
Any</p></td>

    <td id='Row3Column4' >


<a name="wp7613"></a><p class="pTableCell">
Route</p></td>

    <td id='Row3Column5' >


<a name="wp7615"></a><p class="pTableCell">
Any</p></td>

    <td id='Row3Column6' >


<a name="wp7617"></a><p class="pTableCell">
Route</p></td>

    <td id='Row3Column7' >


<a name="wp7619"></a><p class="pTableCell">
Normal*</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7621"></a><p class="pTableCell">
No</p></td>

    <td id='Row4Column2' >


<a name="wp7623"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row4Column3' >


<a name="wp7625"></a><p class="pTableCell">
Any</p></td>

    <td id='Row4Column4' >


<a name="wp7627"></a><p class="pTableCell">
Route</p></td>

    <td id='Row4Column5' >


<a name="wp7629"></a><p class="pTableCell">
Any</p></td>

    <td id='Row4Column6' >


<a name="wp7631"></a><p class="pTableCell">
Route</p></td>

    <td id='Row4Column7' >


<a name="wp7633"></a><p class="pTableCell">
Normal*</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row5Column1' >


<a name="wp7635"></a><p class="pTableCell">
No</p></td>

    <td id='Row5Column2' >


<a name="wp7637"></a><p class="pTableCell">
No</p></td>

    <td id='Row5Column3' >


<a name="wp7639"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row5Column4' >


<a name="wp7641"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row5Column5' >


<a name="wp7643"></a><p class="pTableCell">
---</p></td>

    <td id='Row5Column6' >


<a name="wp7645"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row5Column7' >


<a name="wp7647"></a><p class="pTableCell">
Glued</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row6Column1' >


<a name="wp7649"></a><p class="pTableCell">
No</p></td>

    <td id='Row6Column2' >


<a name="wp7651"></a><p class="pTableCell">
No</p></td>

    <td id='Row6Column3' >


<a name="wp7653"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row6Column4' >


<a name="wp7655"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row6Column5' >


<a name="wp7657"></a><p class="pTableCell">
Unprotect</p></td>

    <td id='Row6Column6' >


<a name="wp7659"></a><p class="pTableCell">
Normal </p></td>

    <td id='Row6Column7' >


<a name="wp7661"></a><p class="pTableCell">
Normal**</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row7Column1' >


<a name="wp7663"></a><p class="pTableCell">
No</p></td>

    <td id='Row7Column2' >


<a name="wp7665"></a><p class="pTableCell">
No</p></td>

    <td id='Row7Column3' >


<a name="wp7667"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row7Column4' >


<a name="wp7669"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row7Column5' >


<a name="wp7671"></a><p class="pTableCell">
Unfix</p></td>

    <td id='Row7Column6' >


<a name="wp7673"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row7Column7' >


<a name="wp7675"></a><p class="pTableCell">
Glued</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row8Column1' >


<a name="wp7677"></a><p class="pTableCell">
No</p></td>

    <td id='Row8Column2' >


<a name="wp7679"></a><p class="pTableCell">
No</p></td>

    <td id='Row8Column3' >


<a name="wp7681"></a><p class="pTableCell">
Yes</p></td>

    <td id='Row8Column4' >


<a name="wp7683"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row8Column5' >


<a name="wp7685"></a><p class="pTableCell">
Fix, protect</p></td>

    <td id='Row8Column6' >


<a name="wp7687"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row8Column7' >


<a name="wp7689"></a><p class="pTableCell">
Glued</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row9Column1' >


<a name="wp7691"></a><p class="pTableCell">
No</p></td>

    <td id='Row9Column2' >


<a name="wp7693"></a><p class="pTableCell">
No</p></td>

    <td id='Row9Column3' >


<a name="wp7695"></a><p class="pTableCell">
No</p></td>

    <td id='Row9Column4' >


<a name="wp7697"></a><p class="pTableCell">
Normal </p></td>

    <td id='Row9Column5' >


<a name="wp7699"></a><p class="pTableCell">
---</p></td>

    <td id='Row9Column6' >


<a name="wp7701"></a><p class="pTableCell">
Normal </p></td>

    <td id='Row9Column7' >


<a name="wp7703"></a><p class="pTableCell">
Normal </p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row10Column1' >


<a name="wp7705"></a><p class="pTableCell">
No</p></td>

    <td id='Row10Column2' >


<a name="wp7707"></a><p class="pTableCell">
No</p></td>

    <td id='Row10Column3' >


<a name="wp7709"></a><p class="pTableCell">
No</p></td>

    <td id='Row10Column4' >


<a name="wp7711"></a><p class="pTableCell">
Normal </p></td>

    <td id='Row10Column5' >


<a name="wp7713"></a><p class="pTableCell">
Fix, protect</p></td>

    <td id='Row10Column6' >


<a name="wp7715"></a><p class="pTableCell">
Protect</p></td>

    <td id='Row10Column7' >


<a name="wp7717"></a><p class="pTableCell">
Glued</p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pHTaskSubhead">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7719"></a><p class="pBody">

* If defined in the original PADS Layout design, the glue status of the via is lost. The test point is preserved by SPECCTRA and is returned to the PADS Layout design.
</p>

<a name="wp7720"></a><p class="pBody">

** You can delete the via in SPECCTRA if the route, edit, or clean commands are performed in SPECCTRA after the Unprotect command.
</p>

<a name="wp7746"></a><p class="pHTaskSubhead">

Unroutes
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8763"></a><p class="pTableTitle" id="MGC8763">

Table 13-4. <a name="CRefID63488"></a>
Protection Status for Unroutes
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8763table7721">
  <tr bgcolor="#CCCCCC"  align="center" valign="middle">
    <th>

<a name="wp7723"></a><p class="pTableHeading" id="MGC8763">
Type of Unroute in PADS Layout
</p>
</th>

    <th>

<a name="wp7725"></a><p class="pTableHeading">

Passed to SPECCTRA as
</p>
</th>

    <th>

<a name="wp7727"></a><p class="pTableHeading">

Returned from 
<br />SPECCTRA as
</p>
</th>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:2.07in'>


<a name="wp7729"></a><p class="pTableCell">
Not protected unroute</p></td>

    <td id='Row2Column2'  style='width:1.69in'>


<a name="wp7731"></a><p class="pTableCell">
No special handling</p></td>

    <td id='Row2Column3'  style='width:2.24in'>


<a name="wp7733"></a><p class="pTableCell">
No special handling</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7735"></a><p class="pTableCell">
Protected totally unrouted connection</p></td>

    <td id='Row3Column2' >


<a name="wp7737"></a><p class="pTableCell">
Fromto type, Fix</p></td>

    <td id='Row3Column3' >


<a name="wp7739"></a><p class="pTableCell">
No special handling. Not protected in PADS Layout</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7741"></a><p class="pTableCell">
Protected unroutes of partially routed connections</p></td>

    <td id='Row4Column2' >


<a name="wp7743"></a><p class="pTableCell">
No special handling</p></td>

    <td id='Row4Column3' >


<a name="wp7745"></a><p class="pTableCell">
No special handling</p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pHTaskSubhead">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7747"></a><h3 class="pHeading4 FontLevel3" id="MGC7747">


Passing Physical Design Reuses to SPECCTRA
</h3>
<a name="wp7750"></a><p class="pBody">



Routes that are elements of a physical design reuse are passed to SPECCTRA with a <span class=" cItalic">fix</span> attribute. Therefore, you cannot modify or route them. SPECCTRA only connects to vias and coppers in a physical design reuse if they are passed with a <span class=" cItalic">route</span> attribute. <a href="xlater2.html#wp8769"  onclick='oT("CRF","xlater2.html#wp8769");return false;'>Table&#160;13-5</a> provides a summary of Physical Design Reuse Processing.
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8769"></a><p class="pTableTitle" id="MGC8769">

Table 13-5. 
Physical Reuse Processing<a name="CRefID21483"></a>
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8769table7751">
  <tr bgcolor="#CCCCCC"  align="center" valign="middle">
    <th>

<a name="wp7753"></a><p class="pTableHeading" id="MGC8769">

<br />Reuse Element
</p>
</th>

    <th>

<a name="wp7755"></a><p class="pTableHeading">

Passed to SPECCTRA as
</p>
</th>

    <th>

<a name="wp7757"></a><p class="pTableHeading">

Returned from SPECCTRA 
</p>
</th>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:2.07in'>


<a name="wp7759"></a><p class="pTableCell">
Component</p></td>

    <td id='Row2Column2'  style='width:1.69in'>


<a name="wp7761"></a><p class="pTableCell">
lock_type fix</p></td>

    <td id='Row2Column3'  style='width:2.24in'>


<a name="wp7763"></a><p class="pTableCell">
No
<br />(Warning issued; whether it has changed, or not, the new 
<br />placement is not returned to PADS Layout.)</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7765"></a><p class="pTableCell">
Via</p></td>

    <td id='Row3Column2' >


<a name="wp7767"></a><p class="pTableCell">
type route</p></td>

    <td id='Row3Column3' >


<a name="wp7769"></a><p class="pTableCell">
No</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7771"></a><p class="pTableCell">
Trace</p></td>

    <td id='Row4Column2' >


<a name="wp7773"></a><p class="pTableCell">
type fix</p></td>

    <td id='Row4Column3' >


<a name="wp7775"></a><p class="pTableCell">
No</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row5Column1' >


<a name="wp7777"></a><p class="pTableCell">
Jumper</p></td>

    <td id='Row5Column2' >


<a name="wp7779"></a><p class="pTableCell">
lock_type fix</p></td>

    <td id='Row5Column3' >


<a name="wp7781"></a><p class="pTableCell">
No</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row6Column1' >


<a name="wp7783"></a><p class="pTableCell">
Copper with netname</p></td>

    <td id='Row6Column2' >


<a name="wp7785"></a><p class="pTableCell">
type route</p></td>

    <td id='Row6Column3' >


<a name="wp7787"></a><p class="pTableCell">
No</p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pBody">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7790"></a><h3 class="pHeading4 FontLevel3" id="MGC7790">


Passing Jumpers to SPECCTRA


</h3>
<a name="wp7791"></a><p class="pBody">

You can pass jumpers to SPECCTRA. SPECCTRA will not attempt to route PADS Layout jumpers.
</p>

<table class="notes">
  <tr class="NotesUpperRuleBlack">
    <td class="NotesUpperRule" colspan='2'><span class="cNotesBlack"><img src="../MGC/images/blank2x2.png" /></span></td>
  </tr>
  <tr class="NotesNote">
    <td class="NoteTip"></td>
    <td valign="top">
            
<a name="wp8786"></a><p class="pnoteInfo">

        <span class=" cBold">	Tip: </span>Do not use SPECCTRA jumpers; they are not backward compatible.
<br />
        </p>
          </td>
  </tr>
  <tr class="NotesBottomRuleBlack">
    <td class="NotesBottomRule" colspan='2'>&nbsp;</td>
    </tr>
 </table><a name="EW33"></a>
<a name="wp7796"></a><h2 class="pHeading3NoSplit WarninG FontLevel2" id="MGC7796">

<a name="CRefID61805"></a>
SPECCTRA and Split/Mixed Planes


</h2>
<a name="wp7797"></a><p class="pBody">

To attach power nets to plane polygons in SPECCTRA, use one of the following split plane definition methods:
</p>

<a name="wp7798"></a>
<ul><li class="LL1BulSolid">If you typically define split planes after you route your designs in SPECCTRA, see the <span class=" cLinkOverride"><a href="../padslayout_ref/nsmgchelp.htm" target="_top"  onClick='oT("STD","DefiningSplitPlanesAfterRoutinginSPECCTRA","padslayout_ref");return false;' >Defining Split Planes After Routing in SPECCTRA</a></span> topic.</li></ul>

<a name="wp23842"></a>
<ul><li class="LL1BulSolid">If you typically define split planes before you route your designs in SPECCTRA, see the <span class=" cLinkOverride"><a href="../padslayout_ref/nsmgchelp.htm" target="_top"  onClick='oT("STD","DefiningSplitPlanesBeforeRoutinginSPECCTRA","padslayout_ref");return false;' >Defining Split Planes Before Routing in SPECCTRA</a></span> topic.</li></ul>

<a name="wp23844"></a><p class="pBody">

SPECCTRA translates split/mixed plane layers without routing, named copper, or plane polygons as power layers. SPECCTRA does not consider power layers as routing layers and, therefore, cannot route on these layers. This minimizes the layer count passed to the router. For example, you can route a four-layer design with two power layers in a SPECCTRA configuration licensed for two routing layers.
</p>

<a name="wp7801"></a><p class="pBody">

SPECCTRA regards the entire plane as the area in which to connect component pins to all plane nets. The SPECCTRA fanout and route commands connect SMD component pins by routing short traces from the pins to vias to satisfy a connection to the plane.
</p>

<a name="wp7802"></a><p class="pBody">

For best results:
</p>

<a name="wp7803"></a>
<ul><li class="LL1BulSolid">Perform a multipass fanout of power pins before you execute multiple route passes by inserting the number of fanout passes in the command. For example, change &quot;fanout (pin_type power)&quot; to &quot;fanout 5 (pin_type power)&quot;.</li></ul>

<a name="wp7804"></a><p class="pBody">

Select the proper fanout options as defined in the &quot;Do File Editor&quot; topic in the <span class=" cItalic">  SPECCTRA Link Help</span>. 
</p>

<a name="wp7805"></a>
<ul><li class="LL1BulSolid">Avoid assigning design rules to nets that are associated with split/mixed plane layers. If design rules are present the design will not open in SPECCTRA. The SPECCTRA Link automatically removes or ignores design rules associated with split/mixed plane layers.</li></ul>
<a name="EW34"></a>
<a name="wp7806"></a><h3 class="pHeading4 WarninG FontLevel3" id="MGC7806">


Routed Traces on PADS Layout Split/Mixed Plane Layers
</h3>
<a name="wp7807"></a><p class="pBody">

With PADS Layout you can route traces on split/mixed plane layers. This is also possible in SPECCTRA, but the file is automatically adjusted to achieve the proper results in SPECCTRA. These changes result in behavior modifications of the routing commands in SPECCTRA, possibly causing unexpected routing patterns.
</p>

<a name="wp7808"></a><h3 class="pHeading4 FontLevel3" id="MGC7808">


Adjustments to the Design
</h3>
<a name="wp7809"></a><p class="pBody">

SPECCTRA translates PADS Layout split/mixed plane layers with routing or named copper as mixed, rather than power layers. Therefore, SPECCTRA routes on these layers, if necessary, to complete the design.
</p>

<a name="wp7810"></a><h3 class="pHeading4 FontLevel3" id="MGC7810">


Behavior Changes in SPECCTRA
</h3>
<a name="wp7811"></a><p class="pBody">

Mixed layers are translated as routing layers, increasing the layer count passed to SPECCTRA. For example, a four-layer design with two routing layers, one power layer, and one mixed layer is considered a three routing layer design and cannot be opened in a SPECCTRA configuration that is licensed for only two routing layers.
</p>

<a name="wp7812"></a><p class="pBody">

SPECCTRA considers plane polygons on mixed layers as areas available for connecting component pins to the plane net, but does not consider them obstacles to routing. Therefore, the fanout and route commands can add routes that pass through the plane polygons on SPECCTRA mixed layers.
</p>

<a name="wp7813"></a><p class="pBody">

Isolated instances of routing failure may occur. Failures may include the failure of the fanout command to connect pins to the plane polygons, or when the route command moves a connected plane net pin outside the area defined by the plane polygon, thus isolating the pin from the plane net.
</p>

<a name="wp7815"></a><p class="pBody">


To avoid the behavior changes, use one of the following procedures in your design process:
</p>

<a name="wp7818"></a>
<ul><li class="LL1BulSolid">Split the planes after routing. For more information, see <a href="xlater2.html#wp7796"  onclick='oT("CRF","xlater2.html#wp7796");return false;'>&quot;SPECCTRA and Split/Mixed Planes&quot;</a>.</li></ul>

<a name="wp7820"></a>
<ul><li class="LL1BulSolid">Unroute the offending traces before proceeding. Prior to passing the design to SPECCTRA, unroute any traces in the split/mixed layers. Remove any named copper. After routing in SPECCTRA completes and the design returns to PADS Layout, reroute the traces you previously unrouted and restore the named copper shapes to the proper split/mixed layer.</li></ul>

<a name="wp7822"></a><h2 class="pHeading3NoSplit FontLevel2" id="MGC7822">

<a name="CRefID84438"></a>
PADS Layout to SPECCTRA Rules Conversion

</h2>
<a name="wp7824"></a><p class="pBody">


Design Rules are converted into one of two types of SPECCTRA rules using the keywords RULE and CIRCUIT. The type used in the conversion is indicated for each SPECCTRA rule.
</p>

<a name="wp7825"></a><h3 class="pHeading4 FontLevel3" id="MGC7825">


Routing, High-Speed, and Clearance Rules
</h3>
<a name="wp7826"></a><p class="pBody">

Routing, high-speed, and clearance rules are supported for classes, nets, groups, and pin pairs. Additionally, as <a href="xlater2.html#wp8775"  onclick='oT("CRF","xlater2.html#wp8775");return false;'>Table&#160;13-6</a> shows, PADS Layout default rules are passed when possible.
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8775"></a><p class="pTableTitle" id="MGC8775">

Table 13-6. <a name="CRefID45187"></a>
Routing Rules&#160;
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8775table7827">
  <tr bgcolor="#CCCCCC"  align="center" valign="middle">
    <th>

<a name="wp7829"></a><p class="pTableHeading" id="MGC8775">
PADS Layout Routing Rules
</p>
</th>

    <th>

<a name="wp7831"></a><p class="pTableHeading">

SPECCTRA Routing Rules
</p>
</th>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:2.375in'>


<a name="wp7833"></a><p class="pTableCell">
Copper Sharing</p></td>

    <td id='Row2Column2'  style='width:2.48in'>


<a name="wp7835"></a><p class="pTableCell">
(rule (tjunction on/off))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7837"></a><p class="pTableCell">
Priority</p></td>

    <td id='Row3Column2' >


<a name="wp7839"></a><p class="pTableCell">
(circuit (priority  #))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7841"></a><p class="pTableCell">
Selected Layers*</p></td>

    <td id='Row4Column2' >


<a name="wp7843"></a><p class="pTableCell">
(circuit (use_layer # # #))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row5Column1' >


<a name="wp7845"></a><p class="pTableCell">
Selected Vias*</p></td>

    <td id='Row5Column2' >


<a name="wp7847"></a><p class="pTableCell">
(circuit (use_via a b c))</p></td>


</tr>

  <tr align="left" valign="top">
    <td colspan="2" rowspan="1">

<a name="wp7849"></a><p class="pTableCell">
*Selected Layer and Selected Via rules require the Advanced Rules option in SPECCTRA. </p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pBody">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7852"></a><p class="pBody">

The Link passes default routing rules to SPECCTRA. Copper Sharing is passed at the PCB rule level.
</p>

<a name="wp7853"></a><p class="pBody">

The Link also passes Priority, Selected Layers, and Selected Vias by creating an artificial class containing all nets you did not assign to a class. This artificial class is named CLASS_<span class=" cItalic">nnnnnnn</span>, where <span class=" cItalic">nnnnnnn</span> is a number from 0 to 9999999. The default routing rules are then passed to SPECCTRA in this artificial class, as shown in <a href="xlater2.html#wp8779"  onclick='oT("CRF","xlater2.html#wp8779");return false;'>Table&#160;13-7</a>.
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8779"></a><p class="pTableTitle" id="MGC8779">

Table 13-7. 
High-Speed Rules<a name="CRefID59378"></a>
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8779table7854">
  <tr bgcolor="#CCCCCC"  align="center" valign="middle">
    <th>

<a name="wp7856"></a><p class="pTableHeading" id="MGC8779">
PADS Layout 
<br />High-Speed Rules
</p>
</th>

    <th>

<a name="wp7858"></a><p class="pTableHeading">


<br />SPECCTRA High-Speed Rules
</p>
</th>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:2.625in'>


<a name="wp7860"></a><p class="pTableCell">
Min/Max Length</p></td>

    <td id='Row2Column2'  style='width:3.375in'>


<a name="wp7862"></a><p class="pTableCell">
(circuit (length <span class=" cItalic">max min</span>) (type actual))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7864"></a><p class="pTableCell">
Stub Length</p></td>

    <td id='Row3Column2' >


<a name="wp7866"></a><p class="pTableCell">
(rule (max_stub #))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7868"></a><p class="pTableCell">
Match Lengths</p></td>

    <td id='Row4Column2' >


<a name="wp7870"></a><p class="pTableCell">
(circuit (match_fromto_length <span class=" cItalic">on/off</span>) (tolerance <span class=" cItalic">dist</span>))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row5Column1' >


<a name="wp7872"></a><p class="pTableCell">
Shielding w/Gap</p></td>

    <td id='Row5Column2' >


<a name="wp7874"></a><p class="pTableCell">
(circuit (shield on (use_net <span class=" cItalic">net</span>)))
<br />(rule (shield_gap <span class=" cItalic">dist</span>))
<br />Net must be a power net or SPECCTRA will fail on input.</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row6Column1' >


<a name="wp7876"></a><p class="pTableCell">
Parallelism Length and Gap</p></td>

    <td id='Row6Column2' >


<a name="wp7878"></a><p class="pTableCell">
(rule (parallel_segment (gap <span class=" cItalic">dist</span>) (limit <span class=" cItalic">dist</span>)</p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pBody">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7879"></a><p class="pBody">

The Link passes the default high-speed rules to SPECCTRA. It passes Parallel Length, Tandem Length and Gap, Stub Length, and Min/Max Length by creating an artificial class containing all nets you did not assign to a class. This artificial class is named CLASS_<span class=" cItalic">nnnnnnn</span>, where <span class=" cItalic">nnnnnnn </span>is a number from 0 to 9999999. The high-speed rules are then passed to SPECCTRA in this artificial class.
</p>

<a name="wp7880"></a><h3 class="pHeading4 FontLevel3" id="MGC7880">


Clearance Rules
</h3>
<a name="wp7881"></a><p class="pBody">

As shown in <a href="xlater2.html#wp8783"  onclick='oT("CRF","xlater2.html#wp8783");return false;'>Table&#160;13-8</a>, SPECCTRA accepts only one trace width per rule so the recommended width is passed.
</p>
<div id="TableDivQz"></div>
<div align="center">


<a name="wp8783"></a><p class="pTableTitle" id="MGC8783">

Table 13-8. <a name="CRefID66687"></a>
Clearance Rules&#160;
</p>


<table border="1" cellpadding="5" cellspacing="0" id="wp8783table7882">
  <tr bgcolor="#CCCCCC"  align="center" valign="middle">
    <th>

<a name="wp7884"></a><p class="pTableHeading" id="MGC8783">
PADS Layout
</p>
</th>

    <th>

<a name="wp7886"></a><p class="pTableHeading">

SPECCTRA
</p>
</th>


</tr>

  <tr align="left" valign="top">
    <td id='Row2Column1'  style='width:3.54in'>


<a name="wp7888"></a><p class="pTableCell">
  &#160;</p></td>

    <td id='Row2Column2'  style='width:2.46in'>


<a name="wp7890"></a><p class="pTableCell">
(rule
<br />(width <span class=" cItalic">dist</span>)</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row3Column1' >


<a name="wp7892"></a><p class="pTableCell">
Trace to Trace spacing</p></td>

    <td id='Row3Column2' >


<a name="wp7894"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist</span> (type wire_wire))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row4Column1' >


<a name="wp7896"></a><p class="pTableCell">
Via to Trace spacing</p></td>

    <td id='Row4Column2' >


<a name="wp7898"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist</span> (type via_wire))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row5Column1' >


<a name="wp7900"></a><p class="pTableCell">
Via to Via spacing</p></td>

    <td id='Row5Column2' >


<a name="wp7902"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type via_via))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row6Column1' >


<a name="wp7904"></a><p class="pTableCell">
Pad to Trace spacing</p></td>

    <td id='Row6Column2' >


<a name="wp7906"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type pin_wire))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row7Column1' >


<a name="wp7908"></a><p class="pTableCell">
Pad to Via spacing</p></td>

    <td id='Row7Column2' >


<a name="wp7910"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type pin_via))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row8Column1' >


<a name="wp7912"></a><p class="pTableCell">
Pad to Pad spacing</p></td>

    <td id='Row8Column2' >


<a name="wp7914"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type pin_pin))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row9Column1' >


<a name="wp7916"></a><p class="pTableCell">
Smd to Trace spacing</p></td>

    <td id='Row9Column2' >


<a name="wp7918"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type smd_wire))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row10Column1' >


<a name="wp7920"></a><p class="pTableCell">
Smd to Via spacing</p></td>

    <td id='Row10Column2' >


<a name="wp7922"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type smd_via))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row11Column1' >


<a name="wp7924"></a><p class="pTableCell">
Smd to Pad spacing</p></td>

    <td id='Row11Column2' >


<a name="wp7926"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type smd_pin))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row12Column1' >


<a name="wp7928"></a><p class="pTableCell">
Smd to SMD spacing</p></td>

    <td id='Row12Column2' >


<a name="wp7930"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type smd_smd))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row13Column1' >


<a name="wp7932"></a><p class="pTableCell">
Board to Trace spacing</p></td>

    <td id='Row13Column2' >


<a name="wp7934"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type area_wire))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row14Column1' >


<a name="wp7936"></a><p class="pTableCell">
Board to Via spacing</p></td>

    <td id='Row14Column2' >


<a name="wp7938"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type area_via))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row15Column1' >


<a name="wp7940"></a><p class="pTableCell">
Board to Pad spacing</p></td>

    <td id='Row15Column2' >


<a name="wp7942"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type area_pin))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row16Column1' >


<a name="wp7944"></a><p class="pTableCell">
Board to SMD spacing</p></td>

    <td id='Row16Column2' >


<a name="wp7946"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type area_smd))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row17Column1' >


<a name="wp7948"></a><p class="pTableCell">
Smd to Via same net</p></td>

    <td id='Row17Column2' >


<a name="wp7950"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type smd_via_same_net))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row18Column1' >


<a name="wp7952"></a><p class="pTableCell">
Smd to Crn same net</p></td>

    <td id='Row18Column2' >


<a name="wp7954"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type smd_to_turn_gap))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row19Column1' >


<a name="wp7956"></a><p class="pTableCell">
Pad to Crn same net</p></td>

    <td id='Row19Column2' >


<a name="wp7958"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type pad_to_turn_gap))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row20Column1' >


<a name="wp7960"></a><p class="pTableCell">
Via to Via same net</p></td>

    <td id='Row20Column2' >


<a name="wp7962"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type via_to_via_same_net))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row21Column1' >


<a name="wp7964"></a><p class="pTableCell">
Drill to Drill spacing</p></td>

    <td id='Row21Column2' >


<a name="wp7966"></a><p class="pTableCell">
(clearance <span class=" cItalic">dist </span>(type drill_gap))</p></td>


</tr>

  <tr align="left" valign="top">
    <td id='Row22Column1' >


<a name="wp7968"></a><p class="pTableCell">
Body to Body spacing</p></td>

    <td id='Row22Column2' >


<a name="wp7970"></a><p class="pTableCell">
Unsupported</p></td>


</tr>


</table>

</div>
<div id='EndTable'> </div>
<p class="pBody">

<br clear='left' class='Blank4Table' />


</p>

<a name="wp7971"></a><p class="pBody">

The Link passes default clearance rules to SPECCTRA at the PCB rule level.
</p>

<table class="notes">
  <tr class="NotesUpperRuleBlack">
    <td class="NotesUpperRule" colspan='2'><span class="cNotesBlack"><img src="../MGC/images/blank2x2.png" /></span></td>
  </tr>
  <tr class="NotesNote">
    <td class="NoteTip"></td>
    <td valign="top">
            
<a name="wp8802"></a><p class="pnoteInfo">

        <span class=" cBold">	Tip</span>: Copper is translated to a SPECCTRA <span class=" cItalic">keepout</span>. In addition, a board outline is translated as a <span class=" cItalic">boundary</span>. Both keepouts and boundaries use the area clearance mentioned above.
        </p>
          </td>
  </tr>
  <tr class="NotesBottomRuleBlack">
    <td class="NotesBottomRule" colspan='2'>&nbsp;</td>
    </tr>
 </table>
<a name="wp7973"></a><h3 class="pHeading4 FontLevel3" id="MGC7973">


Text
</h3>
<a name="wp7974"></a><p class="pBody">

Text translates as a keepout. During generation of the SPECCTRA keepout, the maximum text clearance defined in the following clearance rules is used to expand the SPECCTRA keepout area to allow for the required clearance:
</p>

<a name="wp7975"></a>
<ul><li class="LL1BulSolid">Text-to-Trace spacing</li></ul>

<a name="wp7976"></a>
<ul><li class="LL1BulSolid">Text-to-Via spacing</li></ul>

<a name="wp7977"></a>
<ul><li class="LL1BulSolid">Text-to-Drill spacing</li></ul>

<a name="wp7978"></a>
<ul><li class="LL1BulSolid">Text-to-SMD spacing</li></ul>

<a name="wp7979"></a><h3 class="pHeading4 FontLevel3" id="MGC7979">


Differential Pairs
</h3>
<a name="wp7980"></a><p class="pBody">

SPECCTRA does not support minimum/maximum length directly for differential pairs. However, you can add these restrictions using routing rules applied to the pair of nets.
</p>

<a name="wp7981"></a><p class="pBody">

The following SPECCTRA syntax supports net pairs:
</p>

<a name="wp7982"></a><pre class="pCode">
(pair (nets nm1 nm2 (gap dist)))
</pre>

<a name="wp7983"></a><pre class="pCode">
Pin pairs use the syntax:
</pre>

<a name="wp7984"></a><pre class="pCode">
(pair (wires nm1 nm2 (gap dist)))
</pre>

<a name="wp7985"></a><h3 class="pHeading4 FontLevel3" id="MGC7985">


Conditional Rules
</h3>
<a name="wp7986"></a><p class="pBody">

Conditional rules are separated into two categories: high-speed and clearance. SPECCTRA can accept conditional rules for layers. However, any other rules can only be conditional if they use net classes. A class can contain only nets, not pin pairs or groups. Therefore, any conditional rule that includes a group or pin pair, and is a high-speed rule, cannot be passed to SPECCTRA. 
</p>

<a name="wp7987"></a><p class="pBody">

Nets in conditional rules are automatically placed in dummy SPECCTRA classes using the naming convention NEW_CLASS_# as follows:
</p>

<a name="wp7988"></a><pre class="pCode">
(class NEW_CLASS1 $$$2016)
</pre>

<a name="wp7989"></a><h3 class="pHeading4 FontLevel3" id="MGC7989">


High-Speed Conditional Rules
</h3>
<a name="wp7990"></a><p class="pBody">

A high-speed conditional rule is converted like a nonconditional high-speed rule, except that it must be of the form <span class=" cItalic">class</span> vs. <span class=" cItalic">class</span>, as follows:
</p>

<a name="wp7991"></a><pre class="pCode">
### PADS Layout Conditional Rule ###
</pre>

<a name="wp7992"></a><pre class="pCode">
(class_class
</pre>

<a name="wp7993"></a><pre class="pCode">
(classes CLASS_0 CLASS_1)
</pre>

<a name="wp7994"></a><pre class="pCode">
(rule (parallel_segment (gap dist) (limit dist)))
</pre>

<a name="wp7995"></a><pre class="pCode">
(rule (tandem_segment (gap dist) (limit dist)))
</pre>

<a name="wp7996"></a><pre class="pCode">
)
</pre>

<a name="wp7997"></a><pre class="pCode">
###############################
</pre>

<a name="wp7998"></a><h3 class="pHeading4 FontLevel3" id="MGC7998">


Clearance Conditional Rules
</h3>
<a name="wp7999"></a><p class="pBody">

Conditional clearance rules must be of the form <span class=" cItalic">object vs. layer</span>, as follows:
</p>

<a name="wp8000"></a><pre class="pCode">
###########################
</pre>

<a name="wp8001"></a><pre class="pCode">
### PADS Layout Group Rule ###
</pre>

<a name="wp8002"></a><pre class="pCode">
(group GROUP_0
</pre>

<a name="wp8003"></a><pre class="pCode">
(fromto U2-2 U1-2
</pre>

<a name="wp8004"></a><pre class="pCode">
)
</pre>

<a name="wp8005"></a><pre class="pCode">
(fromto U4-9 U1-9
</pre>

<a name="wp8006"></a><pre class="pCode">
)
</pre>

<a name="wp8007"></a><pre class="pCode">
(fromto U3-10 U4-10
</pre>

<a name="wp8008"></a><pre class="pCode">
)
</pre>

<a name="wp8009"></a><pre class="pCode">
(layer_rule 1
</pre>

<a name="wp8010"></a><pre class="pCode">
(rule
</pre>

<a name="wp8011"></a><pre class="pCode">
(width dist)
</pre>

<a name="wp8012"></a><pre class="pCode">
(clearance dist (type wire_wire))
</pre>

<a name="wp8013"></a><pre class="pCode">
(clearance dist (type via_wire))
</pre>

<a name="wp8014"></a><pre class="pCode">
etc.

</pre>

<table class="notes">
  <tr class="NotesUpperRuleBlack">
    <td class="NotesUpperRule" colspan='2'><span class="cNotesBlack"><img src="../MGC/images/blank2x2.png" /></span></td>
  </tr>
  <tr class="NotesNote">
    <td class="NoteTip"></td>
    <td valign="top">
            
<a name="wp8812"></a><p class="pnoteInfo">

        <span class=" cBold">	Tip</span>: Conditional rules vs. text are ignored. SPECCTRA does not recognize text.
<br />
        </p>
          </td>
  </tr>
  <tr class="NotesBottomRuleBlack">
    <td class="NotesBottomRule" colspan='2'>&nbsp;</td>
    </tr>
 </table>





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